At a remote desert truck stop, the fate of the world will be decided. Evil's armies are amassing. Armed and united by the Archangel Michael, a group of strangers. Legion follows David Haller, a troubled young man who may be more than human. Diagnosed as. Action · David Haller is a troubled young man diagnosed as schizophrenic, but after a strange . Legion -- Comic-Con trailer for " Legion " from FX and Marvel.